Stabilization of an image capture device is desirable when the user is not able to hold the image capture device in a stable position during image capture. If the image capture device is not stable, the captured image may be blurred or otherwise distorted. Such movement is often referred to as “jitter” in the art. Jitter may arise from external sources, such as wind or vibrations from a moving vehicle or the like, or may arise from motion of the user of the image capture device. Such user motion may occur when the user is in a moving vehicle, and/or if the user is physically impaired in a manner that prevents the user from holding the image capture device in a steady position.
Some image capture devices employ stabilization systems to counter the effect of jitter. In some image capture devices, gyroscopes or other physical sensors are employed to detect jitter. One type of image capture device compensates by physically moving one or more components of the image capture device lens system and/or the image capture medium (such as the film or the digital image sensor array). Another type of image capture device compensates for jitter by compensating the digital data corresponding to the capture image.
Some types of image capture devices provide an autofocus system that automatically focuses the image capture device before image capture. Thus, the user of the image capture device does not have to manually focus the image capture device. One type of digital autofocus system evaluates all or part of a series of digitally captured images taken while the lens is moved through some or all of its focus range, and then selects the best “focus” based upon an autofocus correlation algorithm that identifies one or more images that are likely to be focused. That is, the autofocus correlation algorithm determines a desirable “focus value” based upon analysis of image data received from the image capture device photosensor. Then, the image capture device lens unit is adjusted to a focus setting corresponding to the determined focus value. However, capture of a plurality of images and the associated execution of the autofocus correlation algorithm using the image capture device photosensor requires a discernable period of time before image capture occurs.
Another type of autofocus system employs two lens and two corresponding detectors, separated by a distance such that a stereoscopic effect is determinable by the two detectors. The two detectors provide image information that is spatially correlated such that a subject distance is determined. Then, the image capture device lens unit is adjusted to a coarse focus setting corresponding to the determined distance.
Other image capture devices employ both a stereoscopic autofocus system and a digital autofocus system. The stereoscopic autofocus system can provide a relatively quick coarse autofocus adjustment. Then, the digital autofocus system provides a finer focus adjustment. Such hybrid autofocus systems are relatively quicker and more reliable than either the stereoscopic autofocus system and the digital autofocus system alone. However, operation of a hybrid autofocus system still requires a discernable period of time before image capture occurs.